The 2009 TIME 100

Michelle Obama doesn't just inspire us. She affirms us with her intelligence, authenticity, depth and compassion. We see the best of ourselves in her and marvel that no matter what she's doing, she brings 100% of herself to the experience.

I first met Michelle almost five years ago, shortly after Senator Barack Obama's riveting 2004 DNC speech. Long before there was serious talk of a campaign for the presidency, I remember going to the Obamas' house for dinner. I figured there would be takeout since I knew that, like me, Michelle had worked all day. But no, there she was in the kitchen, calm and organized, preparing linguine with shrimp and vegetables.

The woman I witnessed five years ago, with her graciousness, care and attention to detail, is the same woman I visited in the White House in February. Her very presence makes you feel welcome. Her political power is secondary to her heart power, and I salute her for that. I trust her. I know that whatever she gives her attention to, the truth will always be present. She doesn't make false moves.

The joy Michelle, 45, brings to her roles as First Mother and First Lady is what makes her so intoxicating. We want that joy in the roles we inhabit as mothers, wives, workers, daughters and friends. And while we admire those arms and applaud her fashion choices (from J. Crew to top designers), her greatest influence is that she makes us want to be our own best selves — and maybe lift a few weights too.

Watching her on the global stage greeting the Queen and chatting with dignitaries and representing us the way we imagine presenting ourselves on our best day, I was reminded of lines from Maya Angelou's poem "Phenomenal Woman": "It's the fire in my eyes,/ And the flash of my teeth,/ The swing in my waist,/ And the joy in my feet./ I'm a woman/ Phenomenally."

How sweet it is that America has a First Lady who embodies the vibrancy and confidence of a seriously prepared 21st century woman. A phenomenal woman indeed.

Winfrey is a global media leader and international philanthropist

Fast Fact: Michelle Obama's undergraduate thesis for Princeton examined the sometimes isolating experience of being black in the Ivy League